Editor's Choice - Trends in Management and Outcomes of Type B Aortic Dissection: A Report From the International Registry of Aortic Dissection.

OBJECTIVE: To describe the trends in management and outcomes of patients with acute type B aortic dissection in the International Registry of Acute Aortic Dissection. METHODS: From 1996 - 2022, 3 908 patients were divided into similar sized quartiles (T1, T2, T3, and T4). In hospital outcomes were analysed for each quartile. Survival rates following admission were compared using Kaplan-Meier analyses with Mantel-Cox Log rank tests. RESULTS: Endovascular treatment increased from 19.1% in T1 to 37.2% in T4 (ptrend < .001). Correspondingly, medical therapy decreased from 65.7% in T1 to 54.0% in T4 (ptrend < .001), and open surgery from 14.8% in T1 to 7.0% in T4 (ptrend < .001). In hospital mortality decreased in the overall cohort from 10.7% in T1 to 6.1% in T4 (ptrend < .001), as well as in medically, endovascularly and surgically treated patients (ptrend = .017, .033, and .011, respectively). Overall post-admission survival at three years increased (T1: 74.8% vs. T4: 77.3%; p = .006). CONCLUSION: Considerable changes in the management of acute type B aortic dissection were observed over time, with a significant increase in the use of endovascular treatment and a corresponding reduction in open surgery and medical management. These changes were associated with a decreased overall in hospital and three year post-admission mortality rate among quartiles.

Initial Thoracic Endovascular Aortic Repair vs Medical Therapy for Acute Uncomplicated Type B Aortic Dissection.

Importance: Thoracic endovascular aortic repair (TEVAR) has increasingly been used for uncomplicated type B aortic dissection (uTBAD) despite limited supporting data. Objective: To assess whether initial TEVAR following uTBAD is associated with reduced mortality or morbidity compared with medical therapy alone. Design, Setting, and Participants: This cohort study included Centers for Medicare & Medicaid Services inpatient claims data for adults aged 65 years or older with index admissions for acute uTBAD from January 1, 2011, to December 31, 2018, with follow-up available through December 31, 2019. Exposures: Initial TEVAR was defined as TEVAR within 30 days of admission for acute uTBAD. Main Outcomes and Measures: Outcomes included all-cause mortality, cardiovascular hospitalizations, aorta-related and repeated aorta-related hospitalizations, and aortic interventions associated with initial TEVAR vs medical therapy. Propensity score inverse probability weighting was used. Results: Of 7105 patients with eligible index admissions for acute uTBAD, 1140 (16.0%) underwent initial TEVAR (623 [54.6%] female; median age, 74 years [IQR, 68-80 years]) and 5965 (84.0%) did not undergo TEVAR (3344 [56.1%] female; median age, 76 years [IQR, 69-83 years]). Receipt of TEVAR was associated with region (vs South; Midwest: adjusted odds ratio [aOR], 0.66 [95% CI, 0.53-0.81]; P < .001; Northeast: aOR, 0.63 [95% CI, 0.50-0.79]; P < .001), Medicaid dual eligibility (aOR, 0.76; 95% CI, 0.63-0.91; P = .003), hypertension (aOR, 1.26; 95% CI, 1.03-1.54; P = .03), peripheral vascular disease (aOR, 1.24; 95% CI, 1.02-1.49; P = .03), and year of admission (2012, 2013, 2014, and 2015 were associated with greater odds of TEVAR compared with 2011). After inverse probability weighting, mortality was similar for the 2 strategies up to 5 years (hazard ratio [HR], 0.95; 95% CI, 0.85-1.06), as were aorta-related hospitalizations (HR, 1.12; 95% CI, 0.99-1.27), aortic interventions (HR, 1.01; 95% CI, 0.84-1.20), and cardiovascular hospitalizations (HR, 1.05; 95% CI, 0.93-1.20). In a sensitivity analysis that included deaths within the first 30 days, initial TEVAR was associated with lower mortality over a period of 1 year (adjusted HR [aHR], 0.86; 95% CI, 0.75-0.99; P = .03), 2 years (aHR, 0.85; 95% CI, 0.75-0.96; P = .008), and 5 years (aHR, 0.87; 95% CI, 0.80-0.96; P = .004). Conclusions and Relevance: In this study, 16.0% of patients underwent initial TEVAR within 30 days of uTBAD, and receipt of initial TEVAR was associated with hypertension, peripheral vascular disease, region, Medicaid dual eligibility, and year of admission. Initial TEVAR was not associated with improved mortality or reduced hospitalizations or aortic interventions over a period of 5 years, but in a sensitivity analysis that included deaths within the first 30 days, initial TEVAR was associated with lower mortality. These findings, along with cost-effectiveness and quality of life, should be assessed in a prospective trial in the US population.

Knowledge gaps in surgical management for aortic dissection.

Aortic dissection (AD) is recognized as a potentially fatal condition and its standard treatment has been surgical intervention for acute type A AD (TAAD) and complicated acute type B AD (TBAD), and medical management for uncomplicated acute type B AD. Due to rapidly evolving device technologies and minimally invasive surgical techniques that have lowered perioperative risk, there are paradigm shifts for the indications and treatment options for both TAAD and TBAD. In this article, we will discuss the current indications and treatment options for TAAD and TBAD by chronicity of the disease, which comprises four categories: acute TAAD, chronic (repaired) TAAD, acute TBAD, and chronic TBAD. We will also discuss the knowledge gaps in the current surgical management strategies and literature evidence. Open surgical intervention remains the reference standard for acute TAAD and chronic TAAD with complications until an endoprosthesis that will suit the complex anatomy of aortic root, ascending aorta, and aortic arch is developed. Thoracic endovascular aortic repair is now the first line for complicated acute and chronic TBADs. However, we need a larger trials to support the safety and durability of the procedures in patients with uncomplicated TBAD. Without additional data, patients are left to choose between existing treatment options, such as open surgical repair and stent-grafting.

A mixed method approach to understanding the impact of COVID-19 on patients with or at risk for aortic dissection.

Aortic dissection (AD) is a life-threatening rare disease that occurs as a spontaneous tear in the wall of the aorta. Survivors of AD go on to have a chronic disease process that requires lifelong follow-up and management. Although the COVID-19 pandemic has strained health systems and impacted practice in the United States, the effects of these impacts on people living with or at risk for AD is not well understood. This mixed methods project examined the experiences of people in the AD community during the COVID-19 pandemic between March and October 2020. Results reveal that the AD community lacked clear guidance on the role aortic health status plays in COVID-19 risk and experienced significant disruptions in aortic healthcare. At the same time, the new expansion in access to medical care with telehealth conferred unforeseen benefits in the form of reduced barriers for access to specialized aortic health care.

Modified Banding of Arteriovenous Fistulas for the Treatment of Vascular Access Induced Digital Ischaemia.

OBJECTIVE: Vascular access induced digital ischaemia is an uncommon complication of haemodialysis access procedures and is difficult to manage. Several techniques have been described to treat this phenomenon, with variable long term success. Although all of these procedures have been shown to work, they have a significant failure rate, such as persistent high vascular access flow or loss of access. One of the major technical limitations of these techniques is the lack of quantitative data gathered during the procedure to ensure treatment success. In this study, the aim was to describe a novel technique that can improve the success of banding in preserving access and eliminating digital ischaemia. TECHNIQUE: A modified method for arteriovenous fistula banding that incorporates measurements of distal arterial pressure to improve the success of the procedure is described. RESULTS: Sixteen patients with vascular access induced digital ischaemia and high-flow vascular access were treated using the technique. All procedures were technically successful. At 30 days, complete symptomatic relief (clinical success) was seen in 81% (n = 13) of patients. There was no access thrombosis or infection in any of the patients at the 30 day follow up. Six month follow up data were available in seven patients. There was no loss of access patency or recurrence of symptoms observed at six months. CONCLUSION: This novel technique is simple and effective and can be used safely as first line therapy for the management of vascular access induced digital ischaemia.

Scoping review of non-thermal technologies for endovenous ablation for treatment of venous insufficiency.

INTRODUCTION: The aim of this review article was to compare the outcomes of newer non-thermal endovenous ablation techniques to thermal ablation techniques for the treatment of symptomatic venous insufficiency. EVIDENCE ACQUISITION: Three independent reviewers screened PubMed and EMBASE databases to identify relevant studies. A total of 1173 articles were identified from database search that met our inclusion criteria. Two articles were identified through reference search. Removal of duplicates from our original search yielded 695 articles. We then screened these articles and assessed 173 full-text articles for eligibility. Subsequent to exclusion, 11 full-text articles were selected for final inclusion. EVIDENCE SYNTHESIS: The non-thermal techniques are similar to thermal techniques in terms of a high technical success rate, closure rate at 12 months, change in Venous Clinical Severity Score and change in quality of life after procedure. However, the length of procedure is shorter for non-thermal modalities and patient comfort is improved with lower pain scores. Return to work may also be earlier after non-thermal ablation. The rates of bruising, phlebitis and paresthesia are higher after thermal ablation. CONCLUSIONS: The non-thermal modalities are safe and effective in treating venous reflux and have shown improved patient comfort and shorter length of procedure which may make them favorable for use compared to the thermal modalities.

Maturation Rates of Arteriovenous Fistulas Using Small Veins in the Era of Endovascular Interventions.

BACKGROUND: Traditional practice suggests the abandonment of veins smaller than 3 mm in diameter for arteriovenous fistula (AVF) creation because of a low rate of maturation. This study aims to show that with balloon-assisted maturation (BAM), undersized veins can be used to create functional AVFs with a high rate of success. METHODS: All patients who underwent AVF creation between 2014 and 2018 at a tertiary academic medical center were retrospectively reviewed. The patients without preoperative vein mapping, those who failed to follow-up, and the patients who were not on dialysis were excluded. A fistula was considered to be mature if it was successfully cannulated for dialysis. A total of 596 patients were identified for analysis. The cohort was divided into the small-vein group (SVG, <2.5 mm) and large-vein group (LVG, ≥2.5 mm) based on preoperative vein size. Categorical variables were analyzed with the chi-squared test for their association with maturation status. Continuous variables were analyzed with the Wilcoxon rank sum test. A P-value less than 0.05 was considered significant. RESULTS: In the study cohort, 61.9% of the patients were male, with an average age of 62.8 ± 13.7 years, and an average preoperative vein size of 2.9 ± 1.1 mm. With similar demographic distribution, the participants in the SVG (n = 216) had significantly smaller preoperative vein size of 1.9 ± 0.4 mm than the patients in the LVG (n = 380), 3.5 ± 0.8 mm (P = 0.001). There were significantly more radio-cephalic AVFs created in the SVG (77.8% versus 48.7%, P < 0.0001). The overall maturation rate was 83.1% (n = 495), 219 fistulas (36.7%) matured primarily and 276 (46.3%) required interventions. Ninety-one percent of the patients required only 1 or 2 BAMs to achieve maturation. The SVG achieved a maturation rate of 75.9% as compared with 87.1% in the LVG (P = 0.002). A significantly higher number of patients in the SVG required BAM for maturation as compared with the LVG (67.7% versus 49.9%, P = 0.0002); however, there was no difference in the average number of BAMs required for fistula maturation between the groups (1.5 ± 0.8 for the SVG vs. 1.4 ± 0.7 for the LVG). In multivariable logistic regression analysis, vein size ≥2.5 mm (odds ratio (OR) = 2.11, confidence interval (CI): 1.36-3.27, P = 0.0009) and male sex (OR = 2.30, CI: 1.49-3.57, P = 0.0002) were independent predictors of maturation. CONCLUSIONS: Small veins can be used for AVF creation with lower but still favorable maturation rates using BAM interventions, especially in male patients. This practice can increase the creation of autogenous dialysis access and potentially reduce complications related to prosthetic dialysis access.

Acute Arterial Thromboembolism in Patients with COVID-19 in the New York City Area.

BACKGROUND: Coronavirus disease 2019 (COVID-19) predisposes to arterial and venous thromboembolic complications. We describe the clinical presentation, management, and outcomes of acute arterial ischemia and concomitant infection at the epicenter of cases in the United States. METHODS: Patients with confirmed COVID-19 infection between March 1, 2020 and May 15, 2020 with an acute arterial thromboembolic event were reviewed. Data collected included demographics, anatomical location of the thromboembolism, treatments, and outcomes. RESULTS: Over the 11-week period, the Northwell Health System cared for 12,630 hospitalized patients with COVID-19. A total of 49 patients with arterial thromboembolism and confirmed COVID-19 were identified. The median age was 67 years (58-75) and 37 (76%) were men. The most common preexisting conditions were hypertension (53%) and diabetes (35%). The median D-dimer level was 2,673 ng/mL (723-7,139). The distribution of thromboembolic events included upper 7 (14%) and lower 35 (71%) extremity ischemia, bowel ischemia 2 (4%), and cerebral ischemia 5 (10%). Six patients (12%) had thrombus in multiple locations. Concomitant deep vein thrombosis was found in 8 patients (16%). Twenty-two (45%) patients presented with signs of acute arterial ischemia and were subsequently diagnosed with COVID-19. The remaining 27 (55%) developed ischemia during hospitalization. Revascularization was performed in 13 (27%) patients, primary amputation in 5 (10%), administration of systemic tissue- plasminogen activator in 3 (6%), and 28 (57%) were treated with systemic anticoagulation only. The rate of limb loss was 18%. Twenty-one patients (46%) died in the hospital. Twenty-five (51%) were successfully discharged, and 3 patients are still in the hospital. CONCLUSIONS: While the mechanism of thromboembolic events in patients with COVID-19 remains unclear, the occurrence of such complication is associated with acute arterial ischemia which results in a high limb loss and mortality.

The Role of Duplex Ultrasound in Assessing AVF Maturation.

BACKGROUND: Arteriovenous fistulas (AVFs) are favored for hemodialysis (HD) access. However, in many instances, AVFs fail to mature. We examined the utility of postoperative color duplex ultrasound (CDU) in assessing AVF maturation and determining the need for balloon-assisted maturation (BAM). METHODS: A total of 633 patients underwent AVF creation at a single institution from 2015 to 2018. A total of 339 patients (54%) underwent CDU at a median of 8 weeks postoperatively. We collected the following parameters: vein diameter, volume flow (VF), peak systolic velocities in arterial inflow and venous outflow, and presence of stealing branches. A peak systolic velocity ratio (SVR) of ≥2 correlated with ≥50% stenosis in venous outflow, and SVR ≥3 correlated with ≥50% stenosis at the anastomosis. AVFs were considered mature when they were successfully cannulated on dialysis. A generalized linear mixed model (GLMM) was created to compare duplex criteria associated with successful use of AVF (maturation) to those AVFs that required further intervention or failed to mature. Fistulography images, the current gold standard, were compared with findings from CDU studies to determine validity of the duplex ultrasound. RESULTS: Of the 339 AVFs with postoperative CDU, 31.3% matured without interventions, 38.3% required BAM, 9.7% thrombosed, and the remaining patients were not yet on HD. Based on GLMM analysis, the probability of AVF maturation increases if CDU demonstrated one of the following: the vein diameter is ≥ 6 (odds ratio [OR] = 38.7), no evidence of stenosis in the venous outflow tract (OR = 35.6), no stealing branches (OR = 21.6) and VF ≥ 675 (OR = 5.0). Fistulography was performed in 195 patents. Sensitivity and specificity for each are as follows: vein diameter (84.3%, 28.6%), stenosis (59.3%, 78.8%), and stealing branches (20.7%, 92.7%). CONCLUSIONS: Postoperative CDU should be considered routine to correct anatomical findings that might limit AVF maturation and identify the need for further interventions.

Cleaning Up the MESS: Can Machine Learning Be Used to Predict Lower Extremity Amputation after Trauma-Associated Arterial Injury?

BACKGROUND: Thirty years after the Mangled Extremity Severity Score was developed, advances in vascular, trauma, and orthopaedic surgery have rendered the sensitivity of this score obsolete. A significant number of patients receive amputation during subsequent admissions, which are often missed in the analysis of amputation at the index admission. We aimed to identify risk factors for and predict amputation on initial admission or within 30 days of discharge (peritraumatic amputation [PTA]). STUDY DESIGN: The Nationwide Readmission Database for 2016 and 2017 was used in our analysis. Factors associated with PTA were identified. We used XGBoost, random forest, and logistic regression methods to develop a framework for machine learning-based prediction models for PTA. RESULTS: We identified 1,098 adult patients with traumatic lower extremity fracture and arterial injuries; 206 underwent amputation. One hundred and seventy-six patients (85.4%) underwent amputation during the index admission and 30 (14.6%) underwent amputation within a 30-day readmission period. After identifying factors associated with PTA, we constructed machine learning models based on random forest, XGBoost, and logistic regression to predict PTA. We discovered that logistic regression had the most robust predictive ability, with an accuracy of 0.88, sensitivity of 0.47, and specificity of 0.98. We then built on the logistic regression by the NearMiss algorithm, increasing sensitivity to 0.71, but decreasing accuracy to 0.74 and specificity to 0.75. CONCLUSIONS: Machine learning-based prediction models combined with sampling algorithms (such as the NearMiss algorithm in this study), can help identify patients with traumatic arterial injuries at high risk for amputation and guide targeted intervention in the modern age of vascular surgery.

Management of retrograde type A IMH with acute arch tear/type B dissection.

The incidence of intramural hematomas (IMH) in acute dissection (AD) patients varies between 6% and 30% in the literature, most frequently involving only the descending aorta (58%) than the arch or ascending aorta (42%). In this setting, IMH that initiate in the descending aorta, but extend into the arch or ascending aorta have been described, and referred to as a retrograde type A IMH. In these patients the risk of neurological or cardiac complications are high, and therefore an open surgical or hybrid approach has been proposed as the most appropriate. Nevertheless, the endovascular management of such lesions in surgically unfit patients for open surgery have been offered with acceptable outcomes, although the risk of landing in an unsuitable proximal landing zone is evident. In conclusion, retro-TAIMH is an acute aortic syndrome and should be managed as such. The recommended treatment strategy is open surgery for treating ascending or arch involvement, and TEVAR/medical, based on a complication-specific approach, for those with only descending localization. In those patients in whom retro-TAIMH is associated with an acute B dissection presenting with a proximal entry tear located into the descending aorta, a TEVAR represents an option treatment.

The Society for Vascular Surgery practice guidelines on follow-up after vascular surgery arterial procedures

Although follow-up after open surgical and endovascular procedures is generally regarded as an important part of the care provided by vascular surgeons, there are no detailed or comprehensive guidelines that specify the optimal approaches with regard to testing methods, indications for reintervention, and follow-up intervals. To provide guidance to the vascular surgeon, the Clinical Practice Council of the Society for Vascular Surgery appointed an expert panel and a methodologist to review the current clinical evidence and to develop recommendations for follow-up after vascular surgery procedures. For those procedures for which high-quality evidence was not available, recommendations were based on observational studies, committee consensus, and indirect evidence. Recognizing that there are numerous published reports on the role of duplex ultrasound for surveillance of infrainguinal vein bypass grafts, the Society commissioned a systematic review and meta-analysis on this topic. The panel classified the strength of each recommendation and the corresponding quality of evidence on the basis of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system: recommendations were graded either strong or weak, and the quality of evidence was graded high, moderate, or low. The resulting recommendations represent a wide variety of open surgical and endovascular procedures involving the extracranial carotid artery, thoracic and abdominal aorta, mesenteric and renal arteries, and lower extremity arterial revascularization. The panel also identified many areas in which there was a lack of high-quality evidence to support their recommendations. This suggests that there are opportunities for further clinical research on testing methods, threshold criteria, and the role of surveillance as well as on the modes of failure and indications for reintervention after vascular surgery procedures.

The Society for Vascular Surgery practice guidelines on follow-up after vascular surgery arterial procedures.

Although follow-up after open surgical and endovascular procedures is generally regarded as an important part of the care provided by vascular surgeons, there are no detailed or comprehensive guidelines that specify the optimal approaches with regard to testing methods, indications for reintervention, and follow-up intervals. To provide guidance to the vascular surgeon, the Clinical Practice Council of the Society for Vascular Surgery appointed an expert panel and a methodologist to review the current clinical evidence and to develop recommendations for follow-up after vascular surgery procedures. For those procedures for which high-quality evidence was not available, recommendations were based on observational studies, committee consensus, and indirect evidence. Recognizing that there are numerous published reports on the role of duplex ultrasound for surveillance of infrainguinal vein bypass grafts, the Society commissioned a systematic review and meta-analysis on this topic. The panel classified the strength of each recommendation and the corresponding quality of evidence on the basis of the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system: recommendations were graded either strong or weak, and the quality of evidence was graded high, moderate, or low. The resulting recommendations represent a wide variety of open surgical and endovascular procedures involving the extracranial carotid artery, thoracic and abdominal aorta, mesenteric and renal arteries, and lower extremity arterial revascularization. The panel also identified many areas in which there was a lack of high-quality evidence to support their recommendations. This suggests that there are opportunities for further clinical research on testing methods, threshold criteria, and the role of surveillance as well as on the modes of failure and indications for reintervention after vascular surgery procedures.

New predictors of complications in carotid body tumor resection.

OBJECTIVE: This study examined the relationship between two new variables, tumor distance to base of skull (DTBOS) and tumor volume, with complications of carotid body tumor (CBT) resection, including bleeding and cranial nerve injury. METHODS: Patients who underwent CBT resection between 2004 and 2014 were studied using a standardized, multi-institutional database. Demographic, perioperative, and outcomes data were collected. CBT measurements were determined from computed tomography, magnetic resonance imaging, and ultrasound examination. RESULTS: There were 356 CBTs resected in 332 patients (mean age, 51 years; 72% female); 32% were classified as Shamblin I, 43% as Shamblin II, and 23% as Shamblin III. The mean DTBOS was 3.3 cm (standard deviation [SD], 2.1; range, 0-10), and the mean tumor volume was 209.7 cm3 (SD, 266.7; range, 1.1-1642.0 cm3). The mean estimated blood loss (EBL) was 257 mL (SD, 426; range, 0-3500 mL). Twenty-four percent of patients had cranial nerve injuries. The most common cranial nerves injured were the hypoglossal (10%), vagus (11%), and superior laryngeal (5%) nerves. Both Shamblin grade and DTBOS were statistically significantly correlated with EBL of surgery and cranial nerve injuries, whereas tumor volume was statistically significantly correlated with EBL. The logistic model for predicting blood loss and cranial nerve injury with all three variables-Shamblin, DTBOS, and volume (R2 = 0.171, 0.221, respectively)-was superior to a model with Shamblin alone (R2 = 0.043, 0.091, respectively). After adjusting for Shamblin grade and volume, every 1-cm decrease in DTBOS was associated with 1.8 times increase in risk of >250 mL of blood loss (95% confidence interval, 1.25-2.55) and 1.5 times increased risk of cranial nerve injury (95% confidence interval, 1.19-1.92). CONCLUSIONS: This large study of CBTs demonstrates the value of preoperatively determining tumor dimensions and how far the tumor is located from the base of the skull. DTBOS and tumor volume, when used in combination with the Shamblin grade, better predict bleeding and cranial nerve injury risk. Furthermore, surgical resection before expansion toward the base of the skull reduces complications as every 1-cm decrease in the distance to the skull base results in 1.8 times increase in >250 mL of blood loss and 1.5 times increased risk of cranial nerve injury.

Percutaneous fenestrated endovascular aortic graft treatment of aortocaval fistula with aortic pseudoaneurysms secondary to penetrating trauma.

Aortocaval fistula (ACF) is a lethal complication of aortic aneurysmal disease. Traditional treatment of ACF involves open surgical approaches to fistula ligation and repair of the great vessels, with a high mortality secondary to bleeding and cardiac compromise. We present the case of a 28-year-old man with a chronic ACF with concomitant aortic pseudoaneurysms secondary to penetrating trauma treated with a fenestrated endograft.

Feasibility of a proposed randomized trial in patients with uncomplicated descending thoracic aortic dissection: Results of worldwide survey.

The trial we propose will be the first multicenter, randomized, trial investigating the role of thoracic endovascular aortic repair (TEVAR) of uncomplicated type B aortic dissection (TBAD) compared to conservative (medical) management. To document the current management approaches for uncomplicated TBAD, we performed an international survey in 130 centers (in US and worldwide), of whom 114 (89%) responded. Sixty-three (54.8%) respondents do not routinely stent uncomplicated TBAD, and 43 (37.4%) perform TEVAR based on various imaging criteria. One hundred and one respondents (88.6%) agreed that equipoise was present. Almost all respondents agreed that demonstrating an improvement in major aortic complication-free survival with TBAD would lead to change in practice. The results of the survey demonstrate that a major randomized trial to determine the optimal management strategy for uncomplicated TBAD is warranted.